Waste-heat boiler system



, H. KOPPERS WASTE HEAT BOILER SYSTEM Filed July '7.- 1921 .'5 Sheets-Sheet 1 RR v Dec. 27, 1927. 1,653,635

y H. KOPPE RS WASTE HEAT BOILER SYSTEH Filed July '7. 1921 5 Sheets-Sheet 2 O [W6/Zr- Dec. 27, 1927.

H. KOPPERS WASTE HEAT BOILER SYSTEM Filed July '7. 1921 3 Sheets-Sheet 5 IIJ\|\1 4 ldlIIlI-Illl Patented Dec. 27, 1927.

UNITED STATES- HEINRICH IKOIPPERS,u OF ESSEN-RUHIR.v GERMANY, ASSIGNOR lT THE KOEPERS'I-I]-V OF PITTSBURGH, PENNSYLVANIA, A CORPORATION *VELOIMENT CORPORATION..

OF PENNSYLVANIA.

PATENT OFFICE.

WASTE-HEAT BOILER SYSTEM.

'Application led July 7, 1921, Serial No. 4831352, and in Germany October 21, 1919.

ther advantage .that a relatively-high steam` IA pressure and super-heating are attained.l

In spite" of the use of careful heat4 insulation and skilfully carried out heat recovery, approximately 50% of heat-is lost, owing to radiation and waste heat losses," in

"-0 regenerative hearth ovens aswell as steel melting ovens. It is Well'lmown to pass the waste heat gases from .an oven first through regenerators thereof and then through a steam boiler plant: it is also well known to utilize the great heat radiating surfaces, particularly the arches of the ovens, for developing steamfby associating pipes or boilers 'with such radiating surfaces. An economical utilization of heat by either of these methods Ais notI possible be.

cause. in the first method, kthe waste gases have been soAreduced in heat inpassing first through ther regenerators that by the time the waste gases Areach the steam boiler plant the temperature of the gases has been reduced so much that they dd not have the high de# gree of heat necessary for producing steam of, -a certain pressure and for superheating such steam, and because, inthe second method the radiant heat while possibly producing steam does not'ihave the` high vdegreev of .heat necessary forproducing steam of high pressure and for superheatingv such steam. The lack of such high degree of heat, as is well known, is the reason why large quantities oft heat of low'degree, for instance the vheat of the Sun, cannot be utilized in'a practical manner lfor industrial purposes. Now, the invention not only con- .50 sists in using jointly the radiant heat from the oven andthe heat from the waste gases, but also in bringingabout the use of `the latter source of heat. ina special manner. As far back as the German Patent 196,532,

it has been pointed out that the utilization of the Waste heatfor preheating fuels has entirely natural-restrictions imposed on itowing to the limited capacity of the-fuels to absorb heat, andvforl that reason the rule was laid down that a part of thefwaste heat be branched oii" at a high temperature stage and diverted vfrom entry into' the regenera-4 tors and used as separate effective heat. In

this manner, what is practically the same heat surplus, is obtained but with a high degree of heat. This idea is also made use of in the present case by so connecting a steam boiler plant with the hearthv or tub oven that both the radiating heat of the oven.

particularly ofthe oven-ceiling, and also the heat surplus of the waste heat which 'is branched ofi at any one time before entering the regenerators. are utilized for producing steam. This can take place in such a Wav that a preheater'charged witlrwater and exposed to the radiation of the oven arch is connected-` with a boiler which is heated with the said separated high degree heat. so that in the boiler a lively development of steam and. occasion arising. a superheating. take place by .virtue of the higher l degree of the Autilized heat actingion the pre-heated Water. l

In the .drawings a st 'le of embodiment of the inventive idea is reproduced for the purpose of explanation. in which drawings-- Fig. 1- is-a longitudinal vertical section of a hearth oven andconnected parts embody- 1 ing the invention;

. Fig'. 2 is a vertical cross section of the same'. the. heat-retaining coverv beingfomitted for clearness. f

Fig. 3 is a plan view of the same. the top v enclosure or 'casing being removed.

The hearth or tub oven a is connected by the flues b and c with the regenerators d and e situated underneath the latter and 'serving in the well known manner at one time as air and gas heaters and at another as waste heat storers. When these functions are alternated. which happens about every half hour. the direction of the flame lin the ovena is reversed accordingly. On the oven arch f Vthe preheater g in theform of a pipe grate'is so supported that the .water content in it is highly heated by the radiating ovenheat. By t-hepipesz and la this preheater g is connected with two boilers l and m the lan advantageous effect as regards the hearthboilers.

heat flues ot which, by means of slides or valves n and 0 can beconnected with or cut oft from the main flue 79 leading to the vchirn'- ney. The tire boxes g and r of these boilers are provided with bent connections s and t leading` from the hearth chamber a so that, according to the position of the slides n and o, a part of the waste heat is withdrawn directly through one of the boilers Z or m to the chimney. On account of the whigh temperature of this waste heat-about 1000 degresan energetic steam production can be letected.

The boiler plant in this connection is solidly connected with the-foundation and upper enclosure a of the oven and conveniently contained therein in such a way that heat losses owing to conduction and radiation are avoided. For ovens which have their own movement, tor instance tilting Martin ovens, the connections to the boiler are to be placed in such a way that this movementis re'n dered possible. This Larrangement ,also has oven plant in itselfin that the checkerwork ot the regenerators acted on by the smaller quantity ot gas, is lessapt to be obstructed by flue dust, thus being made to'last better and longer. Since, furthermore, the waste heat gases in the heat recovery plant are` now also utilized more perfectly, they impart less heat to the altern'atingly acting regencrators and other parts, so that the diiiiculties, hitherto caused by over-heating ofy the same are eliminated. Y

It will be understood that while either previously heated regencrator is heating 'the fuel which is on its way to the hearth, the

other regcncrator-is connected as indicated' diagrammatically at T. with the chimney indicated diagrammatically at 'S .and 'is being heated by such portionl of the products of combustion as doesnot pass to the boiler;

'and the two regenerators and boilers func-y tion alternately in this manner.

'lVhat is claimed is- 1. In combination with a hearth oven; reversible regenerators communicably connected with said oven 'and operatively vdisposed into inow and outflow groups; boilers; means for conducting a portion of the waste heat through said regenerators; means for conducting thel surplus of said waste 'heat from the oven directly through saidl boilers; land a preheater exposed to and at fected by the radiating yheat otthe oven, said preheater being. connected with said boilers to supply preheated water to said 2. The combination of an oven, reversible regenerators communicably connected with.

said oven and operatively disposed into inlow and loutflow groups, the connections between the regenerators and the oven' constituting means tor supplying fuel to said oven through said regenerators, a chimney, means for conductmg products of Combustion from the oven through said regeneraconnected with said boilers to supply preheated water thereto.

3. In combination with a hearth oven:

'reversible regenerators communicably connected with said oven landoperatively disposed into inlow and outflow groups; boilers adapted to be heated in alternation by waste gas from said ovengmeans for conducting a portion of the waste gas from lthe oven' through said regenerators; means for conducting the surplus of such waste gas trom the oven directly through said boilers; means for controlling How through said last mentioned means; and a. preheater exposed to and affected by the radiating heat of the oven, said preheater being connected with said boilers to supply preheated water to said boilers; said boilers and said preheater being solidly connected with the oven foundation vand so associated therewith as to prevent loss of radiating heat irrespective of the hearth being lixedor movable.

4. The combination ot an oven, reversible regenerators communicably connected with said oven and operatively disposed into in-..

low and outflow groups, the connections between the regen-erators and the oven constituting means for supplying fuel to said oven through said regenerators, a chimney, means for conducting products of' combustion from the oven through said regenerators alternately to the chimney, boilers having heating lues, means for diverting from said regenerators portions ot Jthe products of combustion and causing them to pass through said boiler-heating iues, a preheater heated by the oven and connected with said boilers to supply preheated kwater thereto;

and an enclosure including the top of the` oven and said boilers. y

5.` In combination vwithfa hearth oven: reversible regenerators communicably connected with said oven and operativelyfdisposed into iniow and outflow groups; aboil-l er having means for conductingy thereto from said oven a ortion of the waste heat which l is the'rebyfdiverted from entering said -regenerators; and a preheater outside of and near said oven and heated by the radiant l heat therefrom and communicating with said boiler to supply preheated water thereto.

6. In combination .with Aan open hearth y oven, two sets of regenerators, a boiler assoelated w1th each set, two waste gas condults extending from sald oven, each conduit having a leg communicating with one of said'.

,and a. preheater exposed to radiant heat from said oven and 1n communication with each of sald boilers.

7. In combination wlth an oven: reversible regenerators communicably connected with said oven and operatively disposed into Viniow and 'outflow groups; boilers; a preheater connected with said boilers to supply preheated water to said boilers,4 said preheater being exposed to and heated by the heat radiating from the oven, and m'eans whereby separate effective waste heat. of the oven which is diverted from entering the regenerators. f

HEINRICH KOPPERS..

said boilers maybe heated by the` 

